Liposarcoma in the Extremity / 대한골관절종양학회지

PURPOSE: We analyzed disease free survival and the prognostic factors of liposarcoma in the extremity. MATERIALS AND METHODS: Between 1994 and 2005, of 44 patients who were diagnosed and treated for liposarcoma of the extremity, 40 patients were restrospectively analysed. 13 out of 40 patients got postoperative radiotherapy. We examined local recurrence, distant metastasis and disease free 5-year survival rate. We also analyzed clinical prognostic factors, such as age, gender, size of tumor, prior unplanned excision, histologic type, surgical excision margin and postoperative radiotherapy respectively. RESULTS: There were 3 cases of local recurrence and 4 cases of distant metastasis. The disease free 5-year survival rate was 85.0%. 26 patients presented with myxoid, 8 well differentiated, 4 round cell, 1 pleomorphic and 1 dedifferentiated histology. The disease free 5-year survival rate of mixoid, well differentiated and round cell liposarcoma were 100.0%, 84.6% and 75.0% (p=0.419). The 5-year disease free survival rate was 90.6% in negative surgical margin (n=25) and 62.5% in positive surgical margin (n=15) (p=0.003). CONCLUSION: Our study suggests that surgical excision margin is significant prognostic factor for 5-year disease free survival rate.

Antibiotic Microbial Prophylaxis for Spinal Surgery: Comparison between 48 and 72-Hour AMP Protocols

STUDY DESIGN: This is a prospective randomized cohort study. PURPOSE: We intended to evaluate the efficacy of a 48 hour antibiotic microbial prophylaxis (AMP) protocol as compared with a 72 hour AMP protocol. OVERVIEW OF LITERATURE: The current guideline for the prevention of surgical site infection (SSI) suggests the AMP should not exceed 24 hours after clean surgery like spinal surgery. But there exist some confusion in real clinical practice about the duration of postoperative antibiotic administration because the evidence of the guideline was not robust. METHODS: The subjects were 548 patients who underwent spinal surgery at our department from April 2007 to December 2008. The patients were classified into two groups according to the prophylaxis protocol: group A, for which AMP was employed for 72 hours postoperatively and group B, for which AMP was employed for 48 hours postoperatively. Five hundred two patients out of 548 patients were followed until 6 months postoperatively. The incidence of SSI in the two groups was analyzed. RESULTS: The overall infection rate was 0.8%. There was no significant difference in infection rate between the two groups. The overall infection rate for the patients who underwent instrumented fusion was 0.9%. There was no significant difference in the infection rate between the patients of the two groups who underwent instrumented fusion. CONCLUSIONS: AMP for 48 hours is as efficient as AMP for 72 hours.

Tissue Engineering of the Intervertebral Disc with Cultured Nucleus Pulposus Cells Using Atelocollagen Scaffold and Gene Therapy

STUDY DESIGN: This is an in-vitro experiment using rabbit intervertebral disc (IVD) cells and growth factors. OBJECTIVES: We wanted to determine the effect of types I, and II atelocollagen and growth factor gene therapy for matrix regeneration of rabbit IVD cells. SUMMARY OF THE LITERATURE REVIEW: Adenovirus-medicated growth factor gene therapy is efficient for matrix regeneration of the IVD. Atellocollagen has provided a favorable environment for matrix synthesis. However, a combined approach using gene and cell therapy in an atelocollagen scaffold has not yet been attempted. MATERIALS AND METHODS: Rabbit IVD cells were transduced with Ad/TGF-beta1 and Ad/BMP-2. The cells were then implanted to the atelocollagen scaffold. The [methyl-3H]thymidine incorporation for DNA synthesis and the [35S]sulfur incorporation for proteoglycan synthesis were measured. RT-PCR was performed for assessing the aggrecan, collagen type I, collagen type II and osteocalcin mRNA expressions. RESULTS: The rabbit IVD cells with Ad/TGF-beta1 and that were cultured in type I atelocollagen showed a 130% increase in new proteoglycan synthesis, while the rabbit IVD cells with Ad/TGF-beta1 and that were cultured in type II atelocollagen showed a 180% increase in new proteoglycan synthesis (p<0.05). The rabbit IVD cells with Ad/BMP-2 and that were cultured in type I atelocollagen showed a 70% increase in new proteoglycan synthesis, while the rabbit IVD cells with Ad/BMP-2 and that were cultured in type II atelocollagen showed a 95% increase (p<0.05). Rabbit IVD cells with Ad/TGF-beta1 and Ad/BMP-2 and that were cultured in type I and II atelocollagen demonstrated increased collagen type I and II mRNA expressions without an osteocalcin mRNA expression (p<0.05). CONCLUSION: Cell and gene therapy in an atelocollagen scaffold provided a efficient mechanism for chondrogenic matrix regeneration of rabbit IVD cells.